Ball valves are utilized in a variety of different applications including acting as check valves in excess flow situations.
A typical shut off ball valve assembly is found in Gute, U.S. Pat. No. 5,107,890. Gute teaches a check valve having a body member, conical spring, check ball and valve seat, including a coined seating surface to reduce leakage. Other typical ball valve assemblies can be found in Holt, U.S. Pat. No. 4,830,046 and Peters, U.S. Pat. No. 4,010,770.
The present invention is unique in both is design and its function. The present invention allows control of fluid flow without the use of the springs taught in other check valves. In place of springs, the present invention employs a series of by-pass ports that allow the flow of fluids during normal operating flow rates while preventing the flow of fluids beyond a predetermined threshold flow rate.
One embodiment of the present invention incorporates the by-pass ports as part of one central aperture. This simplicity of design allows one to control fluid flow without the springs and multiple apertures taught by previous inventions.
Furthermore, the present invention was specially designed to be used in conjunction with hot gas filtering systems, where ceramic candle filters are used. Many candle filters found in hot gas systems are constructed of brittle ceramic materials that easily break apart and allow particulate laden hot gas to enter the clean side of the filtering system. No previous ball valve has been specifically designed for use in conjunction with a hot gas filtering system that utilizes a ceramic filter.
There is need for a device that is specifically designed to shut off gas flow and prevent contamination of hot gas filtering systems, in the event that a ceramic candle filter breaks.